In wireless communication systems, parameter measurement is essential to the efficient operation of the system. These parameters include, bit error rates (BERs), block error rates (BLERs), signal to interference ratio (SIR) measurements, Doppler shifts, etc. To illustrate, in many wireless communication systems, the block error rate is used to determine whether transmission power levels need to be increased or decreased. A high BLER results in an increase in power and a low BLER results in a decrease in power. The use of the BLER measurements helps the wireless system maintain an efficient trade-off between transmission power levels and system capacity.
In certain situations, these parameters are difficult to measure. To illustrate, the BLER for a voice service is desired to be measured at a 95% confidence level. A number of Cyclic Redundancy Check (CRC) errors is used as the BLER measure. If the quality target is 10−2, it takes approximately 700 measurements to estimate the error within ±0.01 with 95% confidence. Accordingly, 700 (CRC) blocks need to be evaluated. For typical voice communication, two CRC's may occur every 40 ms. As a result, it takes fourteen seconds to reach a 95% confidence level for the BLER. For a fast moving mobile, channel conditions can change considerably in fourteen seconds. A mobile moving at 100 kilometers per hour will travel approximately 0.4 km in that time period. Accordingly, the channel conditions at two locations 0.4 km apart may be totally different. Additionally, a quick fade, such as a one second fade, could occur during that period, making the calculated BLER erroneous.
Accordingly, it is desirable to have alternate approaches to measuring such parameters.